PROJECT SUMMARY Black women are disproportionately diagnosed with human immunodeficiency virus (HIV) and sexually transmitted infections (STIs). Black women often contract HIV/STIs through high-risk sex and adolescence is when these behaviors are more common. Furthermore, Black adolescent girls are more affected by HIV/STIs than other demographics of adolescent girls; yet, there are few engaging and effective interventions designed exclusively for them. In fact, many are unaware of their partner HIV/STI status and do not consistently use condoms to protect themselves. Therefore, interventions that counter individual-level risk perception by promoting HIV/STI testing for themselves and their partners and reduce risk behaviors, such as non-condom use, are greatly needed. There is compelling evidence that peers play a significant role in the protection from risk associated with HIV/STIs by providing opportunities to exchange knowledge, influence attitudes, and to develop new behavioral skills. Videogame interventions, which are frequently played with others, can be culturally tailored, provide behavioral skills training, and have demonstrated efficacy in affecting health behaviors related to health promotion. With the growing evidence for the efficacy of videogames in improving health outcomes, it is essential to examine how to harness these technologies to modify behaviors in Black adolescent girls. With funding from the Women?s Health Research at Yale Pilot Program, the Yale?s play2PREVENT Lab developed and pilot tested a theory-based social card game intervention, One Night Stan, which was aimed at increasing partner HIV/STI testing and condom use in young black women aged 18- 24. Preliminary findings of a pilot study conducted with 21 black women aged 18-21 suggest that playing the game can lead to increased self-efficacy and intentions to use condoms and insist that their partners get tested for HIV across time. In terms of gameplay satisfaction, 100% of participants reported that that they would play the game again, 95% liked the way the game looked, 100% enjoyed playing the game, and 100% reported that they would tell their friends to play. Results from this study suggest that One Night Stan is a feasible intervention approach and may be efficacious in helping players develop a pattern of cognitions and motivation that can protect them against the risk of HIV. Together, a team comprised of experts from the Yale Center for Health & Leaning Games will build upon this formative work and pilot data to adapt One Night Stan to a multiplayer videogame for younger target audience of Black adolescent girls. For this proposal, we will evaluate the feasibility and preliminary efficacy of One Night Stan at increasing self and partner HIV/STI testing by conducting a pilot randomized controlled trial with 80 young Black adolescent girls ages 14-18. We will also explore the efficacy of the intervention for increasing players? HIV/STI knowledge and for increasing intentions and attitudes around safer HIV/STI practices. As a multiplayer videogame, the intervention is a compelling framework for Black adolescent girls who constantly interact and are influenced by their peers.